package cc.comac.mom.config;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import javax.servlet.http.HttpServletResponse;

import org.springframework.stereotype.Service;

@Service
public class UploadPreviewData {

	public static void download(String path,String realName, HttpServletResponse response) {
		
		try {
			// path是指欲下载的文件的路径。
			File file = new File(path);
			// 取得文件名。
			String filename = file.getName();
			// 取得文件的后缀名。
			String ext = filename.substring(filename.lastIndexOf(".") + 1).toUpperCase();
			// 以流的形式下载文件。
			InputStream fis = new BufferedInputStream(new FileInputStream(path));
			byte[] buffer = new byte[fis.available()];
			fis.read(buffer);
			fis.close();
			// 清空response
			response.reset();
			// 设置response的Header
			response.addHeader("Content-Disposition",
					"attachment;filename=" + new String(realName.getBytes("UTF-8"), "ISO8859-1"));
			response.addHeader("Content-Length", "" + file.length());
			OutputStream toClient = new BufferedOutputStream(response.getOutputStream());
			response.setContentType("application/octet-stream");
			toClient.write(buffer);
			toClient.flush();
			toClient.close();
		} catch (IOException ex) {
			ex.printStackTrace();
		}
	}

	public static void previewPdf(String realPath,HttpServletResponse response) {
		File file = new File(realPath);
		if (file.exists()) {
			byte[] data = null;
			try {
				FileInputStream input = new FileInputStream(file);
				data = new byte[input.available()];
				input.read(data);
				response.getOutputStream().write(data);
				input.close();
			} catch (Exception e) {
				e.printStackTrace();
			}
		} else {
			throw new RuntimeException("无法找到当前文件路径");
		}
	}
}
